Oxygen Therapy

Question 1

What are the options for delivering low dose oxygen therapy?

Answer 1

• Low flow nasal cannula
• Simple face mask
• Air-entrainment (venturi) masks

Question 2

What % oxygen does a nasal cannula deliver?

Answer 2

Low flow: 24-40% (1-4L/min)

Humidified high flow: up to 100%

Question 3

What % oxygen does a simple face mask deliver, and when is it used?

Answer 3

28-50%

Imprecise, use in milder situations

Question 4

What % oxygen does a venturi mask deliver and when is it used?

Answer 4

up to 40% (15L/min)

Precise, use for emergencies, hypercapnia, type 2 RF

Question 5

What are the options for delivering high flow oxygen therapy?

Answer 5

• Non-rebreather mask (reservoir)

- High flow humidified nasal cannula

Question 6

What % oxygen does a non-rebreather mask deliver, and when is it used?

Answer 6

60-80% (depending on flow rate and breathing pattern) (15L/min)
Used in emergencies, not controlled as imprecise

Question 7

What is non-invasive ventilation?

Answer 7

The provision of ventilator support through the patients upper airway using a mask. It can be used in hospital or at home for chronic patients

Question 8

What is the difference between positive pressure and negative pressure ventilation?

Answer 8

PP: Air is pushed into the trachea
NP: Air is sucked into the lungs by creation of a vacuum

Question 9

What are the indications for mechanical ventilation?

Answer 9

• Acute lung injury
• Acute severe asthma
• Acute exacerbation COPD
• Neurological (myasthenia gravis, motor neuron disease, spinal cord injury, GB syndrome)
• Significant tachypnea
• Hypoxemia
• Sepsis

Question 10

What are some potential complications of mechanical ventilation?

Answer 10

• Pneumothorax
• Airway injury
• Alveolar damage
• Ventilator-associated pneumonia

Question 11

What is CPAP?

Answer 11

CONTINUOUS POSITIVE AIRWAY PRESSURE

An ‘at home’ machine that increases air pressure in the throat so that the airway doesn’t collapse on inspiration

Uses: Sleep apnoea, acute exacerbation COPD, respiratory failure

Question 12

What is BIPAP?

Answer 12

BILEVEL POSITIVE AIRWAY PRESSURE

A form of non-invasive mechanical pressure support ventilation that uses a time-cycled change between two different applied levels of positive airway pressure

Uses: pneumonia, COPD, asthma

Question 13

What is a rescue pack?

Answer 13

A pack of steroids and antibiotics that you have on standby in case of acute exacerbation of COPD.

Question 14

What is defined as low flow oxygen?

Answer 14

2-6 litres per minute